Air separator for tobacco feed systems

ABSTRACT

Apparatus for pneumatically feeding tobacco to a cigarette making machine includes an air separator comprising a chamber having an inlet of given cross-sectional area for receiving a flow of tobacco carried by air, a deflector which deflects the tobacco along a curved path towards a tobacco outlet, and an air outlet remote from the deflector, the tobacco outlet having a smaller cross-sectional area than the inlet, and the deflector being so shaped that it progressively reduces the transverse dimensions of the tobacco stream with the aid of centrifugal force to enable the tobacco to pass out through the tobacco outlet.

United States Patent 1191 Labbe 1111 3,820,065 1451 July 30, 1974 [5 AIRSEPARATOR FOR TOBACCO FEED 3,514,159 5/1970 Labbe 302/59 SYSTEMS [75]Inventor: Francis Auguste Maurice Labbe, Primary Examine, BemaI-d NozickNemny'sur'seme France Attorney, Agent, or FirmCraig & Antonelli [73]Assignee: Moline Limited, London, England [22] Filed: July 27, 1972 [21Appl. No.: 275,800 [571 ABSTRACT Apparatus for pneumatically feedingtobacco to a cig- [30] Forelgn Application Pnomy Data arette makingmachine includes an airseparator com- July 28, 1971 Great Britain 1.35516/71 prising a chamber having an inlet of given crosssectional areafor receiving a flow of tobacco carried Cl 55/309, 5/4 8, by air, adeflector which deflects the tobacco along 21 55/430, 55/ 131/1 1 4curved path towards a tobacco outlet, and an air out- [51] int. Cl Bold45/12 let remote from the deflector, the tobacco outlet havl l Field ofSearch 131/34 34 10; ing a smaller cross-sectional area than the inlet,and

55/459, 309, 418, 4l3, 461, 458, 432, 460, the deflector being so shapedthat it progressively re- 133 9, 23 duces the transverse dimensions ofthe tobacco stream with the aid of centrifugal force to enable thetobacco [56] References Cited to pass out through the tobacco outlet.

UNITED STATES PATENTS 2,101,249 12/1937 Frisch 209/144 13 Claims, 8Drawing Figures egg? 9 CONTROLLER l A J 25 36 0 /J----- Z0 0 8 1 If I ll 7 6 1 1] 1 l 1 I 1 O 6 1 O t s 7 412 24 \111/ 1 T 4 I 32 E:- l

PATENTED JUL3 01974 3, 826. 065 SHEET 1 or 3 AIR SEPARATOR FOR TOBACCOFEED SYSTEMS This invention is concerned particularly with feedingtobacco by means of air to a cigarette making machine from a primaryunit in which the tobacco may, for example, be loosened and winnowed. Anumber of machines may in practice by supplied by one primary unit. Eachmachine may include a spreading device which spreads the tobaccoreceived from the primary unit into an annular space defined by at leastone rotary member so that a continuous built-up stream of tobacco can bedelivered tangentially from the annular space.

According to one aspect of the invention described in US. ApplicationSer. No. 275,635, a cigarette making system comprises means fordelivering tobacco by means of air into a pipe leading to an airseparator which removes part of the air and passes the tobacco outthrough an outlet, without significantly reducing its velocity, to aspreading device of a cigarette making machine which deflects thetobacco into an annular space defined by at least one moving partarranged to carry the built-up tobacco stream in the annular spacetowards an outlet through which at least part of the built-up tobaccostream is continuously removed, preferably in an approximatelytangential direction.

There is preferably no mechanical seal at the tobacco outlet of the airseparator (such as would reduce the velocity of the tobacco), and theinterior of the spreading device is at a pressure such as not to causeany air flow in through the tobacco outlet of the air separator.Preferably the system operates by means of suction, in which case thesuction pressure in the spreading device should be at least as great asthat in the air separator.

The spreading device may comprise a rotary member including a channelwhich has a tobacco inlet end on the axis of rotation of the rotarymember, and an outlet end spaced from the axis of rotation, so that thetobacco is delivered from the spreading device with a winding action. Bythis means a tobacco stream can be built up in an annular space fromwhich the stream (for example in the form of a carpet) can be fed out ina substantially tangential direction. (A spreading device in this formis described in a patent application filed simultaneously with thepresent application).

According to the present invention an air separator for this purposepreferably comprises a chamber having an inlet of given cross-sectionalarea for receiving a flow of tobacco carried by air, a deflector whichdefleets the tobacco along a curved path towards a tobacco outlet, andan air outlet remote from the deflector, the tobacco outlet having asmaller cross-sectional area than the inlet, and the deflector being soshaped that it progressively reduces the transverse dimensions of thetobacco stream with the aid of centrifugal force to enable the tobaccoto pass out through the tobacco outlet.

According to another aspect of this invention, an air separator for useat the tobacco inlet of a pneumatically fed cigarette making machinecomprises a chamber having an inlet for receiving a flow of tobaccocarried by air, a curved deflector for deflecting the tobacco to atobacco outlet, and an air outlet remote from the deflector, thedeflector being movable (preferably pivotally) so that it can move froma first position, in which it deflects the tobacco to the tobaccooutlet, to a second position in which it deflects the tobacco so that ispasses out through a different'out le't (preferably the air outlet);from this last outlet the tobacco is preferably returned to the primaryunit which delivers tobacco pneumatically to the air separator. Thisaspect of the invention can be applied to a separator such as that shownin British Pat. No. 1,192,177.

In use the deflector is preferably moved to its second positionautomatically when the cigarette making machine stops. Thus there is noneed to arrange that the primary unit stops delivering tobacco assoon'as the making machine stops; the primary unit can instead go ondelivering tobacco, which is returned by the'a'ir sep arator.

The air outlet of the separator may extend from the chamber in adirection transverse to the direction of motion of tobacco through thechamber. In thatcase, in order to deliver the tobacco out through theair outlet when the deflector moves to its second position, there may bea second deflector which, when the first deflector moves to its secondposition, moves to an operative position in which it deflects towardsthe air outlet the tobacco which is deflected past the tobacco outlet bythe first deflector.

Examples of air separators according to this invention are shown in theaccompanying drawings.

In these drawings:

FIG. 1 is a partly sectioned elevation of one separator;

FIG. 2 is a view in the direction of the arrow II in FIG. 1,'showing theair outlet in elevation; FIG. 3 is an enlarged fragmentary section onthe line III--III in FIG. 1;

FIGS. 4 to 6 show how the cross-section of the deflector changes fromone end to the other; and

FIGS. 7 and 8 show different separators.

As shown in FIG. 1, the air separator has an inlet pipe 2 of circularcross-section leading into an approximately cylindrical box 4. One endwall 4A (FIG. 2) is fitted with an air outlet pipe 6 which, at its endadjacent to the wall 4A, is coaxial with the circular peripheral wall ofthe box 4. Part of the peripheral wall of the box is formed by adeflector 8 which deflects the tobacco from the inlet 2 to a tobaccooutlet 10. Most of the air (for example 80 to 90 percent) which carriesthe tobacco in through the inlet 2 is drawn 05 by suction through theoutlet 6. However, some air passes out through the outlet 10 and intothe inlet 12 of a spreading device in which there is a suction pressuresufficient to ensure that air flows outwards through the outlet 10 andinto the separator. For example, the suction pressure in the box 4 maybe mm water gauge, while there is a suction pressure of mm water gaugein the spreading device. The static suction pressure in the spreadingdevice may be less than that in the box 4; however air does flow inwardsthrough the outlet 10 on account of the dynamic pressure head in the box4. Thus the tobacco moves out through the outlet 10 with out beingretarded to any significant extent during its passage through the airseparator. A high-speed knurled roller 13 is mounted at the tobaccooutlet to force the tobacco through the outlet in the event of anymomentary tendency for tobacco to jam in the outlet.

By way of example, the internal diameter of the pipe 2, and the internaldistance between the end walls 4A and 4B of the box 4, may be 76 mm. Airmay pass through the inlet pipe 2 at a rate of 5 ,500 to 7,500 litresper minute and at a velocity of 21 metres per second to carry 6 to 9kilograms per minute of tobacco to the spreading device of a cigarettemaking machine.

The pipe leading to the inlet pipe 2 is gently curved about horizontalaxis below the pipe (assuming the separator is used with its tobaccooutlet 10 extending vertically downwards) so that the tobacco is thrownoutwards by centrifugal force. Thus the tobacco reaches the deflector 8as a somewhat flat, wide, low-density stream 14 (see FIG. 1) lyingagainst the part of the wall of the pipe 2 furthest from the axis of thebox 4.

FIGS. 4 to 6 show how the internal cross-section of the deflector 8changes in the direction of motion of the tobacco so as to convert thetobacco stream from a wide low-density form to a narrower and more densestream which can pass out through the tobacco outlet 10.

On reaching the deflector, the tobacco stream 14 becomes thinner as itis compressed against the deflector by its own inertia. This thinnerstream is then progressively bent into a V-shape (see FIG. 4) and thenmade narrower by the changing cross-section of the deflector.

FIG. 4 shows how the internal cross-section changes progressively from asemi-circular cross-section at A (corresponding to the outer half of thepipe 2) to a slightly rounded V-shape at B. FIG. 5 shows how thecross-section then changes progressively from the rounded V-shape at Bto a narrower shape at C which includes a semi-circular bottom C. Thissemi-circular bottom shape then remains while the sides come togetherprogressively towards the parallel states of the shape D shown in FIG.6, which also shows the knurled roller 13.

Air which passes into the spreading device through the outlet 10 returnsto the separator through a pipe 15 which directs the air axially intothe box so that the air (together with any tobacco entrained in it) canpass straight through the box and into the outlet 6. This is helped bythe fact that the outlet 6 includes a frustoconical end piece 6A (seeFIG. 2).

As shown in FIG. 1, the deflector 8 is pivoted to the box at 16 so thatit can be swung inwards, to the position shown in chain-dotted outline,to deflect the tobacco past the outlet 10. For this purpose the positionof the deflector is controlled by an air cylinder 16A including a pistonrod 18 which is pivoted to the deflector at 20. The air cylinder 16Amoves the deflector 8 inwards automatically in response to a controller17 when the cigarette machine is stopped, so that the delivery oftobacco to the separator by the primary unit does not have to bestopped.

At the same time as the deflector 8 is moved inwards, a second deflector22 moves axially into the box 4 under the control of a second aircylinder 24 in response to the same controller 17. As shown in FIG. 3,the inner edge 22A of the deflector 22 normally lies just within acorrespondingly curved slot in the end wall 48 of the box; the deflectoris carried by a straight member 26 which in turn is carried by posts 28and 30 which can slide axially in bearings 32 and 34. The air cylinder24 includes a piston rod 25 which is connected to the member 26. whenthe deflector 22 moves into the box (to the position shown inchain-dotted outline) it forms a smooth continuation of a part 4C of theperipheral wall of the box. Thus tobacco moving along the wall part 4C,instead of continuing along the wall part 4!), is deflected inwardstowards the air outlet 6. A deflector part 36 serves to deflect thetobacco axially into the outlet 6.

FIG. 7 shows diagrammatically a different separator which is similar tothat shown in FIG. 1, except that instead of the axially movingdeflector 22, a part 38 of the peripheral wall of the box is pivoted at40 so that it can be moved inwards (for example by an air cylinder orother device) to the position shown in chain-dotted outline, so as todeflect the tobacco inwards towards the air outlet 41. A curved part 38Aforms a seal with the edge 43 of the peripheral wall of the box.

FIG. 8 shows a separator which is basically similar to that shown inFIG. 1, except that the axial air outlet is replaced by a tangentialoutlet 42 which starts with a rectangular cross-section so that it has aflat outer wall 44 which forms a tangential extension to the peripheralwall of the box from the point 46. Thus when the deflector 48 movesinwards to carry the tobacco stream past the outlet 50, the tobaccostream automatically passes out through the air outlet 42.

I claim:

1. Apparatus for pneumatically feeding tobacco to a cigarette makingmachine, including an air separator comprising a chamber having an inletof given crosssectional area for receiving a flow of tobacco carried byair, a deflector which deflects the tobacco along a curved path towardsa tobacco outlet, and an air outlet remote from the deflector, thetobacco outlet having a smaller cross-sectional area than the inlet, andthe deflector being so shaped that it progressively reduces thetransverse dimensions of the tobacco stream with the aid of centrifugalforce to enable the tobacco to pass out through the tobacco outlet.

2. Apparatus according to claim 1 in which the inlet to the chamber isof circular cross-section and in which the cross-sectional shape of thedeflector changes progressively from a semi-circular shape, whichcorresponds to half the inlet section, through a substantially V-shapedcross-section, to a narrow trough-shaped cross-section with asemi-circular bottom of smaller radius than the inlet.

3. Apparatus according to claim 2 including a knurled roller whichextends into the narrow troughshaped part of the deflector and is drivenin a direction such as to help to drive tobacco out through the tobaccooutlet in the event of a tendency for tobacco to jam at the outlet.

4. Apparatus according to claim 1 in which at least part of thedeflector is movable to a second position in which it deflects thetobacco so that it passes out through a different outlet.

5. Apparatus according to claim 4 in which the deflector is pivotallymovable about an axis adjacent to the inlet.

6. Apparatus according to claim 4 in which, when the deflector is in itssecond position, the tobacco passes out through the air outlet.

7. A cigarette making system according to claim 4, and including meansfor automatically moving the deflector to its second position inresponse to a signal.

8. Apparatus according to claim 1 in which the air outlet extends fromthe chamger in a direction transverse to the direction of motion oftobacco through the chamber.

9. Apparatus according to claim 8, including a second deflector which,when the first deflector is moved to its second position, can be movedto a position in which it deflects the tobacco into the air outlet.

10. Apparatus according to claim 9 in which the second deflector moveslinearly into the chamber in a direction transverse to the direction ofmotion of the tobacco through the chamber,

11. Apparatus for pneumatically feeding tobacco to a cigarette makingmachine, including an air separator comprising a chamber having an inletfor receiving a flow of tobacco carried by air, a curved deflector fordeflecting the tobacco to a tobacco outlet, and an air passes outthrough the air outlet.

1. Apparatus for pneumatically feeding tobacco to a cigarette makingmachine, including an air separator comprising a chamber having an inletof given cross-sectional area for receiving a flow of tobacco carried byair, a deflector which deflects the tobacco along a curved path towardsa tobacco outlet, and an air outlet remote from the deflector, thetobacco outlet having a smaller cross-sectional area than the inlet, andthe deflector being so shaped that it progressively reduces thetransverse dimensions of the tobacco stream with the aid of centrifugalforce to enable the tobacco to pass out through the tobacco outlet. 2.Apparatus according to claim 1 in which the inlet to the chamber is ofcircular cross-section and in which the cross-sectional shape of thedeflector changes progressively from a semi-circular shape, whichcorresponds to half the inlet section, through a substantially V-shapedcross-section, to a narrow trough-shaped cross-section with asemi-circular bottom of smaller radius than the inlet.
 3. Apparatusaccording to claim 2 including a knurled roller which extends into thenarrow trough-shaped part of the deflector and is driven in a directionsuch as to help to drive tobacco out through the tobacco outlet in theevent of a tendency for tobacco to jam at the outlet.
 4. Apparatusaccording to claim 1 in which at least part of the deflector is movableto a second position in which it deflects the tobacco so that it passesout through a different outlet.
 5. Apparatus according to claim 4 inwhich the deflector is pivotally movable about an axis adjacent to theinlet.
 6. Apparatus according to claim 4 in which, when the deflector isin its second position, the tobacco passes out through the air outlet.7. A cigarette making system according to claim 4, and including meansfor automatically moving the deflector to its second position inresponse to a signal.
 8. Apparatus according to claim 1 in which the airoutlet extends from the chamger in a direction transverse to thedirection of motion of tobacco through the chamber.
 9. Apparatusaccording to claim 8, including a second deflector which, when the firstdeflector is moved to its second position, can be moved to a position inwhich it deflects the tobacco into the air outlet.
 10. Apparatusaccording to claim 9 in which the second deflector moves linearly intothe chamber in a direction transverse to the direction of motion of thetobacco through the chamber.
 11. Apparatus for pneumatically feedingtobacco to a cigarette making machine, including an air separatorcomprising a chamber having an inlet for receiving a flow of tobaccocarried by air, a curved deflector for deflecting the tobacco to atobacco outlet, and an air outlet remote from the tobacco outlet, thedeflector being movable so that it can move from a first position, inwhich it deflects the tobacco to the tobacco outlet, to a secondposition in which it deflects the tobacco so that it passes out througha different outlet.
 12. Apparatus according to claim 11 in which thedeflector is pivotally movable about an axis adjacent to the inlet. 13.Apparatus according to claim 11 in which, when the deflector is in itssecond position, the tobacco passes out through the air outlet.